Muffler.



No. 844,669. PATENTED FEB. 19, 1907.

J. FAIRGHILD. MUFFLER.

APPLICATION FILED FEB.17, 1906.

" ATTORNEY UNITED STATES PATENT OFFICE. I

MUFFLEFL Specification of Letters Patent.

Patented Feb. 19, 1907.

Application filed February 17,1906. Serial Ho. 301,629.

To all whom it may concern.-

Be it known that I, JAMEs E. FAIRCHILD, a citizen of the United States, and a resident in the village of Mamaroneck, county of West chester, State of New York, have invented certain new and useful Improvements in Mufliers, ofwhich the following is a specification, reference 'bein had to the 'accom panying drawings, in which- Figure 1 illustrates a longitudinal vertical section of one form of muffler embodying the invention. Fig. 2illustrates a similar view of a modified construction.

The object of this invention is to provide a muffler which shall be of light weight, comact, low cost, noiseless, or nearly so, and cool. lhe above advantages are realized in mufflers constructed according to this invention to a remarkable degree. i

One form in which the invention may be embodied is shown in Fig. 1, and a modified form in Fig. 2; but the invention is not at all limited to the specific forms shown, as

-will be obvious to those familiar with this art. 1

The essential features mayv be embodied in mechanical constructions uite different from those illustrated, which have shown as examples merely.

Referring first to Fig. 1, AA are two headpieces or disks, which may be circular or any other outline and referably made of aluminium for the sa e of lightness. B is an exterior shell extending between the heads to reduce heat.

' which are preferably A A. C is the inlet from the exhaust-port of the engine. D is an interior or lining shell. E is asbestos, mineral wool, or similar packing F is the expansion-chamber. G G are a series of baffle-plates provided with openings H H H, &c., the total area of which equals and is preferably somewhat greater than the area of the exhaust-inlet is the delivery-port of the muffler. It likewise at least equals, if it does not exceed, the area of the inlet 0. K K K are a series of tubular sections or bushin s which surround the clamping-rod L, whic is pro vided with clamping-n ts M upon each end,

ovided with washers N N. The bushings ii serve to s ace and also support the baflle plates. he first baffle-p ate next the expansion-chamber F, I prefer to make additionally thick, hence strong, as illustrated, in order to withstand the pressure in the expansion-chamber.

It may be additionally supported in such manner as desired.

The operation is as follows: The roducts of combustion passin from the ex aust of the cylinder or cylinders enters the muffler at C and expands in the expansion-chamber F. In order to reduce the heat thus gener ated, the interior lining D and the non-conducting packing E-are supplied. From the expansion-chamber the roducts of the ex haust pass through the 1oles H in the first bafflelate G into the chamber between it andt e next succeeding baflie-plate, and thence in turn throu h the perforations in each of the succee ing baffle-plates and chambers between them. Although their is no prescribed number of perforations necessary per horse-power, I prefer that the perforations should be many and relatively small in each plate. Their total area, however, should at least equal and preferably exceed the area of the inlet 0, so that there shall be free exit ofl the ases, thus avoiding back ressure. Similar y, there is no prescribe number of baffle-plates required; but I have found that the numberillustrated in the drawings-that is to say, tensecures very good results.

My muffler is characterized by the follow in First. Although the motor may be run with sufficient speed to make the exhaust- .pipe connecting the engine-cylinder and muffler very hot, approaching red heat, nevertheless the muffler, except at the front head, will be relatively cool, so that it may be touched by the hand without injury thereto.

Second. The hand may be passed through the exhaust at the tail of the muffler without 9 scorching. This I attribute to the employment'of the non-conducting jacket at the exansion-chamber and to the succession of afile-plates with intervening chambers, in each of which, as is well understood, the charge is successively cooled by reason of its additional expansion.

In Fig. 2 I show a construction practically the same as that above described and illustrated in Fig. 1, exce t-that the exhaust of the engine enters at and escapes from the ex ansion-chamber F to the right and left, as illustrated, and asses out throughthe ex haust-ports P P, t e construction otherwise being, as stated, the same as described in 1 connection with Fig. l. The same number of baffle-plates are also shown; but they are divided and arranged at the right and left of the expansion-chamber F.

I prefer that the expansion. chamber or cylinder should have at least twice the area of the enginecylinder and where com actness is not requisite it may beneficial y be even larger than-this. The non-conducting jacket of asbestos or "-ineral wool not only reduces the heat, but likewise the noise.

The exterior shell B and the interior casing D and the bafiie-plates and spacing-bushings K may all, if preferred, be made of aluminium, as well as the heads, for the sake of lightness; but sheet steel, brass, or galvanized iron may beneficially be used for these parts of the apparatus.

1 do not show any exterior appliances whereby the muffler may be supported or held in proper position relative to the motor or engine because, as is well understood, such means will be varied indifferent constructions, and many suitable appliances for this purpose are now well known and in extensive use.

I claim l. A mufiler embodying a casing closed at each end by a head substantially one half longitudinally of which constitutes an open expansion-chamber with which the exhaust' from the engine-cylinder connects and a series of transverse chambers in the remaining half of the casing which extend across the cylinder from side to side and are separated from each other by baflie-plates, each pro vided with a series of holes the total area of which at least equals that of the engine-exhaust, the end wall of the last of the series of transverse chambers being one of the heads of the casing, which is provided with an exhaust-port.

2. A muffler embod g a closed casing substantially .one ha f longitudinally of which constitutes an open expansion-chamber with which the exhaust from the engine cylinder connects, a non-conducting covering or jacket for the expansion-chamber and a series of transverse chambers in the remaining half of the casing which extend across the cylinder from side to side, the dividing-walls of which are baffle-plates, each provided with a series of holes the total area of which at least equals that of the engine-exhaust, the last of the series oftransverse chambers being provided with an exhaust-port.

3. A mufiier embodying a closed casing made in the form of a cylinder one end of which constitutes an open expansion-chamher with which the exhaust from the engine connects and a series of transverse chambers arranged side by side longitudinally of the cylinder beyond the expansion-chamber and separated from each other by bafile-plates each provided with a series of holes, the total area of which at least equals that of the engine-exhaust, said bafiie-plates beingheld in proper position by a longitudinally-extending rod and intervening spacing blocks or bushings, thelast of the series of transverse chambers having an exhaust-port.

4. A muffler embodying an exterior casing each end of which is closed by a substantial head, substantially one half of the interior of the casing constituting an open expansion-chamber with which the exhaust from the engine-cylinder connects and substantially the other half being divided into a series of transverse chambers, the dividingwalls of which are baffle-plates rovided with holes, the area of which is at east equal to that of the engine-exhaust, and a rod pro- JAMES E. FAIRCHILD.

Witnesses CHAS. SAPORITO, ANDREW S. Comes. 

